NEOTOMA. 73 



Type locality. Tiburon Island, Gulf of California, Mexico. 



Genl. Char. Very like N. albigula; skull has a narrower inter- 

 temporal area; narrower nasals, especially at anterior end. 



Color. Head, entire upperparts and flanks light buff; the hairs on 

 lower back and rump tipped with black, giving these parts a darker hue; 

 entire underparts and inner side of limbs white; hands and feet white; 

 outer side of arms light buff like flanks ; outer side of hind legs darker, 

 like rump; tail above blackish, thinly haired; beneath white; ears 

 naked, dark. Ex type in United States National Museum. 



Measurements. Total length, 334; tail, 154; hind foot, 35. 



This rat in general appearance is almost precisely like N. albigula, 

 but the skull of the type, that of a young adult male exhibits differences 

 as mentioned above. Whether these would retain their comparative 

 dimensions in a series of old adult examples is difficult to determine, 

 but a comparison with such specimens, when obtained, is desirable. 

 The type could not well be separated from N. albigula on its exterior 

 appearance. 



Neotoma insularis Townsend. 



Neotoma insularis Towns., Bull. Am. Mus. Nat. Hist., XXXI, 

 1912, p. 125. 



Type locality. Angel de la Guardia Island, Gulf of California, 

 Mexico. 



Genl. Char. Similar to N. intermedia gilva, but paler. Skull is 

 broader, the rostrum and teeth heavier. 



Color. Entire upperparts and head light buff, lined on lower back 

 and rump with black; entire underparts, inner side of limbs, hands 

 and feet white; outer side of limbs pale buff; tail above very sparsely 

 covered with short white hairs, beneath white. Ex type in United 

 States National Museum. 



Measurements. Total length, 290; tail, 120; hind foot, 35. 

 Skull: Occipito-nasal length, 38.8; Hensel, 36.8; zygomatic width, 

 21.8; intertemporal width, 5.2; length of nasals, 17.6; length of palate, 

 16.7; length of upper molar series, 8.5; length of mandible, 20.6; 

 length of lower molar series, 8.6. Ex type in United States. National 

 Museum . 



Neotoma chrysomelas Allen. 



Neotoma chrysomelas Allen, Bull. Am. Mus. Nat. Hist., XXIV, 

 1908, p. 653. 



Type locality. Matagalpa, Nicaragua. . 



Geogr. Distr. Known only from the type-locality. Altitude 3000 

 feet. 



